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Multiple Coil on Plug failures

This morning, my '05 Escape [V6, 107k miles] died at low speed in traffic. I was able to sort of restart it, and limp back to a nearby Autozone to have the OBD codes read. [after waiting for the store to open].

According to the OBD readout, four of the ignition coils had failed. Counting two prior failures [under warranty], the car has had a total of six failed coils. Presumably today’s failures represented the four original coils.

Since it now looks like six out of six [100%] failure of the original coils, how do I maximize my chances of having Ford [or their supplier] fork over the cash to replace the failed coils?

[Any bargaining ‘stradegy’ that has been effective in similar cases?]

Also, as a virtual show of hands, how troublesome are these coils?

This would be in three categories:

1) General Coil on Plug failures

2) Failures of Ford/Motorcraft parts

3) Failures on the part in the Escape and similar vehicles [Mariner, Tribute, Mazda 6s]

Failure of COPs in the 36K of the warranty are covered. You expect Ford to handle your COP failures at 107K miles under warranty? I’ve had COPs fail, all 8 over a period from 24K to 56K (current) miles on my 2004 T’bird. So I’m aware that COP’s can be problematic. Yet, at 107K miles I know Ford is going to tell me that I am on my own.

I have decided to relace my COP boots (these are the springs with rubber ends that connect the coil and spark plug) every 35K miles. If that works I won’t have to replace the coils themselves. I have priced the coils on Ebay and in case I need to replace all 8 coils myself.

What condition are the spark plugs in? Has it been a few years since the spark plugs were changed? Spark plug condition can affect the cop (coil on plug). Spark plugs which are fouled can have higher resistance which cause the coil voltage to go higher before the spark jumps the gap.

The spark plugs were replaced by the dealer as part of the 100k mile service [last september, plugs are rated for 100k mile intervals]. According to Ford [and the dealer] if the plugs are defective, they are covered by a 12 month /12k mile warranty - but that’s not what the OBD codes indicate has failed.

I may pull the coil and plug for cyl #3, as that is accessible and is still using the original COP.

If it was just a failure of one unit, I would say that was wear and tear. But when four fail at once, and all the original COP units are bad it looks like a bad batch of parts from the supplier.

Nice to see FORD is including ODB2 codes for primary and secondary ignition coil failures (we used to move them around to get a idea of which one failed) what codes led you to the COP failure conclusion? Was any other testing performed? Did the ODB2 code get it right? (just replace the indicated COP and all was well?) This would be very good if the diagnostics got this right.

For the first two failures, the OBD code read at the dealer specified the cylinder number with the bad COP [#5 at about 50k and #1 at about 80k]. Replacing the indicated unit restored the engine to normal performance.

The scanner / software that AutoZone uses is generic, and did not include the cylinder # in the printout.

At my Ford dealer we’ve sold a whopping - 2 - over the past two year sales history. So slow of inventory there are none in stock now.
Not indicative of a wide spread ‘Ford’ nor ‘escape’ problem.

One mistake is allowing plugs to remain in place for 100k miles; rated or not.

Modern plugs have wider gaps. This means the coil (COP or not) has to work harder to provide a spark to jump that gap; and that’s on a new plug and coil.
Throw in age, mileage, long term non-noticeable misfires, along with a widened plug gap and the coil has to struggle even harder.
Eventually something is going to give.

People are also carping over COPs on Nissans, etc. so the same methodogy on plug replacement applies in Nissan’s case.

I lost a couple of COPs when I pressure washed the engine…

There is a Ford TSB 05-11-1, dated 06/13/2005, titled: “MIL ON WITH MULTIPLE COIL PRIMARY DTCS P0351 THROUGH P0356 – 3.0L ENGINE”. All the spark plugs should have a two digit date code. If they don’t, start replacing parts: spark plugs, cops, PCM. So states the TSB.
TSBs usually give you some idea of why the action is necessary. Not this one. Actually, I think that Ford just plain screwed up.

ALWAYS remove the COP or dry it and the hole out before starting after washing an engine. Any tiny crack in the COP + water = a dead COP.

So, my 6 of 6 failure [and UncleTurbo’s 8 of 8 failure] indicates a bad batch?

I’ve found references to TSB 031404, probably TSB 05-11-1 is more of the same

The TSBs have been updated. For the plugs see TSB 09-2-6, and for the coils see TSB 05-22-8.

Remember a TSB is simply a "what to do - if " instructional. If it were a wide spread or high concentration problem , a recall would have been issued.

My Ford garage is a high volume dealer, 24 service bays + 3 quick oil change bays + 3 front end racks, 50 - 80 repair orders written daily . I’ve been here a mere 30 years and have not seen indication of wide spread coil failures. We sell many coils for other applications yet your part number is not even in stock due to low volumes sales numbers.

Hopefully the TSBs will allow someone to repair your vehicle.

Ken, I’ll read those TSBs when I can get to them. It still doesn’t seem reasonable (TSB 05-11-1) to have an engine ignition system that crashes COPs and PCMs because a certain spark plug, with a certain manufactured date, isn’t installed in an engine. Such a narrow design, for mass production isn’t reasonable, or, even rational. It doesn’t matter that later TSBs have different instructions.

I’m not sure how to parse this, something like:

High average reliability * total failure on one vehicle == batch of defective parts used on vehicle.

The [replaced under warranty] new units are not the same as the original [dead] parts